Electrode for luminous-arc electric lamps and process of making the same.



F. BUCHANAN.

ELECTRODE FOR LUMINOUS ARC ELECTRIC LAMPS AND PROCESS OF MAKING THESAME.

' APPLICATION FILED JUNE 19. 1911.

1,25,984. I Patented M12, 191

ATTORNEYS 10R WITNESSES. ivm

FRANK BUCHANAN, OF SYRACUSE, NEW YORK.

Specification of Letters Patent.

Patented Mar. is, rare.

Application filed'J'une 19, 1911. Serial No. 634,019.

To all whom it may concern:

Be it known that I, FRANK BUCHANAN, of Syracuse, in the county ofOnondaga and State of New York, have invented certain new and usefulElectrodes for Luminous- Arc Electric Lamps and Processes of Making theSame, of which the following is a specification.

This invention has for its object the production of an electrode forluminous arm lamps, and it consists in the novel combinations ofelements and the process or steps of combining said elements ashereinafter set forth and claimed.

In describing this invention reference is had to the accompanyingdrawing in which like characters designate corresponding parts in allthe views.

Figure 1 is an elevation, partly in section, of one form of myelectrode.

Fig. 2 is a detail view of the plug at the butt .end of the electrode.

As is well known by those "skilled in the art, metallic oxid electrodesfor luminous arc lamps contain essentially, an iron oxid which givesconductively to the electrode and to the fused mass at the arcing endwhen cold, the other constituents of such electrodes not beingsatisfactory conductors.

In my electrode no iron oxid is used and a conductor of iron is used ofsufficient substance or thickness to not only conduct the current butalso unite with the other material of the electrode to make conductivethe fused mass at the arc end, when cold, and by the use with suchconductor of the filler hereinafter'described, the arc is steady,dimming or dying down thereof at irregular intervals is eliminated, andthe electrode is consumed slowly and evenly. I amunable to state whataction takes place at the are but have discovered that by the use, ofthe ingredients as hereinafer set forth, an electrode of high efiiciencyis produced and a" resultant dry powder is then packed into the metallicconductor. Whether the powder is purely a mechanical mixture or to someextent the product of chemical action. I am unable to state withcertainty but am of the opinion that some chemical action takes Usually,the powdered rutile andelectrode gives a strong white light but consumesmore rapidly than when the ingredients are mixed in'said proportion, andif more than the foregoing proportion is used,

I ELECTRODE FOR LUMINOUS-ARC ELECTRIC LAMPS AND PROCESS OF MAIiIlN'G'IHE SA'ME.

so'that there is an excess of silicate of soda,

the arc is less luminous, and when the saturated mixture is used a verslow consuming electrode of highest e ciency is produced. k

Usually the metallic conductor is a thin tubular iron shell about25/1000 of an inch thick, and the dry powdered mixture of pulverizedrutile and water glass is usually packed into such tube, and the buttend of the tube closed by a plug-and the arc end thereof by a cap.

However, such mixture may be first moldedbinto pencil form and theninserted in the tu e.

In-the drawing 1 designates the tubular metallic shell; 2 the plug atthe butt end of burned through, the metallic shell and the mixturetherein fuses at the arc end of the electrode.

I'have found that an electrode constructed as described will give apractically steady, strong, white light and will last from one and onequarter to twice as long as other luminous arc electrodes operatingunder the same conditions, and will be more perfectly consumed so thatless soot is depositedthan with any other luminous arc electrode.

What I claim is: I 1. An electrode for luminous are electric lampscomprising a metal electric conducting shell, and a dry pulverizedcompound of rutile, and the unevaporative' residue of water glass,intimately commingled, filled within the shell, such shell being ofsutficient substance to carry the current to supply a conductive metalat the arc during the consumption of the electrode, and to render thefused end of the conductor conductive when cold, substantially as andfor the purpose described.

2. An electrode for luminous are electric lamps comprising an iron shellabout twentyfive one-thousandths of an inch thick, and a filler withinthe shell, consisting of powderedf rutile and the unevaporative residueof water glass, intimately commingled, said rutile and residue beingintimately mixed in substantially the proportions of twelve pounds ofrutile with the unevaporated residue, of one quart of water glass,substantially as and for the purpose specified.

3. The herein described process of making electrodes for luminous arclamps consisting in mixing pulverized rutile and water glass insubstantially the proportions herein set forth, into a plastic mass,evaporating the water of the moist mass, pulverizing the dry product,and filling the same into a metallic tube, substantially as and for thepurpose set forth.

4. A slow-consuming luminous are light electrode comprising a metallicshell and a filler composed principally of rutile and sodium silicate,substantially as and for the purpose described.

5. A slow-consuming luminous are light electrode comprising a metallicshell and a filler composed principally of rutile and residue ofwater-glass, substantially as and for the purpose specified.

6. A slow-consuming luminous are light electrode comprising ametallic'shell and a filler composed of intimately mixed and chemicallyuncombined rutile and sodium silicate, substantially as and forthepurpose set forth.

In testimony whereof, I have hereunto signed my name in the presenceoftwo attesting witnesses, at Syracuse, in the county of Onondaga, inthe State of New York, this A 31st day of May, 1911.

FRANK BUCHANAN.

Witnessesz.

S. DAVIS, V Fmnnmuc G. Boom.

